There are many possible causes of car battery failure. It could be the battery itself, or some of the components that work together to charge the battery. Whatever is causing your battery to either fail to be charged or to hold a charge can be found and fixed through a process of elimination.

Causes of battery issues and their solutions

• Battery

If your battery keeps going dead, the first place to look for problems is the battery itself. If your battery is over two years old, or has faced a harsh sub-freezing winter, there is a greater chance that the battery itself needs to be replaced. However, batteries can fail at any age. 

You will need to get your battery checked. Using an adjustable wrench, loosen the nut on the battery mount that holds the battery in place. Then remove the two battery cables, removing the positive cable (on the side of the battery with the plus sign) first, by loosening the nuts that hold the cables in place.

Take the battery to an auto accessories store like United Battery Systems, Inc. and they will usually check your battery for free. If it is bad, they will take your old battery to be recycled. If your battery has a warranty, you will receive a pro-rated refund, depending on how much time is left on the warranty period.

If your battery is good, then you need to look for other reasons for your battery issues such as:

• Corrosion on the battery terminals

This is a common cause of batteries failing to charge. This corrosion, caused by exposure to moisture, resembles a white powder. Before re-installing your battery, use a piece of fine sandpaper to clean all corrosion from the two terminals on top of your battery, and inside the clamps that attach the battery cables to the battery. You may want to purchase a corrosion inhibitor that can be found at an auto accessories store.

• Frayed or damaged battery cables

If your battery cables have bare spots, and the exposed wire touches the metal car body, the battery may lose its charge. Replace the cables if you observe worn spots.

• Loose or worn alternator belt

If the belt that turns your alternator, which charges your battery, is loose or worn, it may need to be replaced. Look at the smaller belt under your hood while the car is running, to see if it is slipping, or listen for a squealing noise that indicates a bad belt. Replace it if necessary.

• Alternator

If the alternator itself is defective, you should see an indicator light on your dash that tells you that it needs to be replaced. You can do it yourself, but it can be difficult to reach. If you lack tools or expertise, you may want to consider  leaving it to a professional.